SCUBA2: only find stats if reporting them
SCUBA2: add support for thresholding at a given signal-to-noise ratio
SCUBA2: new primitive to calculate power spectrum of image

This primitive calculates the azimuthally-averaged spatial power
spectrum for a given image. The peak and half-power length scales are
determined and reported, as is the mean power on a number of scales up
to the filtering scale used in the map maker.
SCUBA2: new primitive to mask emission from an image

This primitive will mask an image using either a signal-to-noise ratio
threshold (default) or using a circular aperture at the map
centre. Default S/N cutoff is 3; default aperture radius is 30
arcsec. Both may be overridden by recipe parameters. The output file
has a suffix of "_mask".